How to generate building on surface
I'm guessing here, but it seems you have buildings made with separate meshes and want to place each building as a complete whole, onto the plane?
If so you can make each building's component a &quot;Child&quot; of a parent, which could be an Empty.  You then move that empty onto the plane and all of the building's components will stick together and follow.
You do the same for each building.
Once each (building) is on the plane, the plane itself can then act as a parent for all of the building-parents, i.e. make a city block which will stick together should you move the plane.
See this answer here -
Partial Rotation
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